Playback troubles XL1

I bought two days ago my XL1, tested it and found out after several recording that while I played back I saw 5 moziac lines on the screen around 5 centimeters high each.
So next day I wen to the shop again and got another XL1, worked great in the beginnening but once in a while has this same error and shows me mozaic lines.
I have to see that I recorded 5 minutes, played back, changed the battery for the adaptor, recorded again etc.

Does anyone has this experience, has it something to do with the timecode on the tape?